Internal-combustion engine



C. O. WYMAN.

INTERNAL coMBusTloN ENGINE.

APPLICATION FILED MAY4|1916. 1,370,939.

2 SHEETS-SHEET 1.

`Patented Mar. 8, 1921.

C. 0. WYMAN.

INTERNAL COMBUSTION ENGINE.

APPLICATION HLED MAY 4. 1916.

Patented Mar. 8, 1921.

2 SHEETS-SHEET 2.

.UNITED STATES f CHARLES OK..WYVMAN, OF vA NOKA, MINNESOTA.

INTERNAL-COMBUSTION ENGINE.

Specication of Letters Patent.

Patented Mar. 8, 1921.

application mea may 4, 191s. serial No. 95,355.

To all wwm it may concern.' v

'Be it known that I, CHARLES O. WYMAN, a citizen ofthe United States, resident of Anoka, county of Anoka, State of Minnesota, have invented certain new and useful Improvements in Internal-Combustion Engines, ofy which the following is a speciication.

My invention relates to engines using gasolene or other suitable explosive as a fuel and the object of my invention is to provide aconstruction by means of which an explosion will occur with each stroke vof the piston, dispensing with the scavenging Stroke usually incidental to engines of the fourcycle type.

A further object is to dispense with the usual cam shafts and operate the valves from the crank shafts, provision being made for an explosion with every revolution of the shaft.

A further object is to provide an engine of comparatively inexpensive construction and of high eiiiciency.

Other objects of the invention will appear from the following detailed description.

The invention consists generally in various constructions and combinations, all as hereinafter described and particularly pointed out in the claim.

' In the accompanying drawings forming part of this specification,

Figure 1 is a vertical sectional view through a cylinder of an internal combustion engine embodying my invention, showing the piston at the beginning of the explosion stroke,

Fig. 2 is a sectional view taken on a line at right angles substantially to the section line of Fig. 1, showing the auxiliary pisto'n at the beginning of the stroke for discharging the burned gases,

Fig. 3 is a view corresponding to Fig.V 2, showing the piston at the beginning of the compression stroke,

Fig. 4 is a vertical Sectiqnal view of a modified construction,

Fig. 5 is a similar view of another modification,

Fig. G'illustrates still another modification.

In the drawing, 2 represents a crank case and 3 the cylinder of an internal combustion engine. Only one cylinder is shown, but it will be understood that any desired number may be used, the structure of all of them being substantially the same. f 4v represents a double crank shaft and 5 the main piston of the engine cylinder having a wrist pin 6 and a connecting rod 7 between the wrist pin and the crank shaft. 8 is an auxiliary piston mounted above the piston 5 and provided with a sleeve 9 which fits within a hole 10 in the wrist pin, the hub 11 of the connecting rod 7 having openings 12 of sufficient width therein to permit the rocking of the hub of the wrist pin in following the stroke of the connecting rod without affecting the sleeve 9. A rod 13 is mounted to telescope with the sleeve 9 and has a rocking` the crank shaft and the rod 21 is actuated by a cam 22a on the shaft 23il that is also geared to the crank shaft. The movement of these valves is so timed that at `the end of the explosion stroke the exhaust valve and the gas intake valve will be opened, as shown in Fig.y 2, one crank of the shaft being a quarter of a revolution ahead of the other crank, so 'that when the auxiliary rod 15 begins its upward movement it will push the auxiliary piston from the position shown in Fig. 2 to that illustrated in Fig. 3. During this initial upward movement of the auxiliary piston the burned gases still in the combustion chamber will be forced out throughk the exhaust valve and a fresh charge will be sucked in to the space between the main piston and the auxiliary piston, as indicated in Fig. 3. `When this charge has entered, `the main piston will begin its upward movement, its crank having passed the center during the upward stroke of the auxiliary piston. When the main piston begins its upward movement, the auxiliary one will nearly have completed its stroke and its movement will be less, and consequently the upward travel of the main piston will open the valve 16 and force the fresh charge of gas through this valve into the space between the head of the cylinder and the auxiliary piston, the exhaust valve in the meantime having closed to preventv the escape of the charge.

itself to the different positions Vof the crank shaft and on the beginning of the upstroke Yof the auxiliary piston the sleeve and rod will be in the position shown in Fig. 2,- where the initial movement of the rod 15 will immediately actuate the auxiliary piston to expel the burned gases from the combustion chamber.

In Fig. 4 I have shown a modified construction, which consists in mounting a cylinder provided with air cocks 26 and 27 and a plunger 28 connected by a rod 29 with an auxiliary piston. The downward movement of the auxiliary .piston will draw the plunger 28 down with it, putting .the air in the lower end of the cylinder 25 under compression so that when the valve 19 is opened to permit the discharge of the. burned gases at the end of the explosion stroke the auxi iliary piston will be raised or drawn away from the main piston to hasten the discharge of the gases throughthe exhaust port.

In Fig. 5 another modification is shown, which consists in mountinga rod 30 on the auxiliary piston to extend up through the head of the cylinder, said rod being pivotally connected to a walking beam 31 which is loosely mounted at 32 upon a rod 33 thatl is slidable in a bracket 34 that is connected by a link 35 with the beam 31. The rod 33 has a hollow end 36 in which a pin 37 is slidable and connected with a crank38 by a rod 39. The pin 37 is positioned to contact with the rod 33 at the end of the hollow-portion thereof to push it upwardly and raise theV auxiliary piston to expel the burned gases when the exhaust valve is opened. This auxiliary piston is forced down with the main piston during the explosion stroke.

In Fig. 6 another modification isshown, in which a walking beam 40 is pivoted on a link 41 that is mounted on the engine cylinder, one end of the beam being connected to the rod 30 on the auxiliary piston and the other end of the beam having a long helical spring 42 connecting it with the crank case, said spring Vnormally tending to raise the auxiliary piston away from the main piston but allowing these two pistons to follow one another on the explosion stroke. In other respects, thelmechanism shown in Fig. 6 is substantially the same as described with reference to the preceding figures.

' In Figs. 1, 2 and 3 the auxiliary piston is shown provided with a boss or projection 43 on the underside thereof to enter a recess 44 in the top of the main piston, these two elements forming a check or buffer in the na- -ture of a dash-pot to prevent shock or jar charge of gas being drawn into the cylinder on the upstroke ,of the main pistonY following the explosion stroke, which is usually required for expelling the waste gasesY after combustion has taken place. As there is van` explosion with every revolution,'it is evident that the cams for operating the valves may beV mounted on the crank shaft, and thereby eliminate, if desired, theuse ofthe cam shafts. y In this application, however, IY have shown the cam shafts geared to the crank shaft to operate atthe same speed, with suitable mechanism between t-he shafts andthe valves.

vIn various ways the details of construcytion herein shown and described may be invention.

. I claim as my invention:

An internal combustion engine comprising a cylinder and a shaft having double cranks thereon, a piston mounted iny said cylinder and having a connecting rod journaled on one of said cranks, an auxiliaryv piston mounted at one. end of said main piston, a connecting rod mounted on the other crank of said shaft and having a sliding connection with said auxiliary piston, movement ofsaid auxiliary piston connecting rod operating to advance said auxiliary piston with respect to said main piston at a predetermined point in the stroke of said main piston.

In witness whereof, I have hereunto set my hand ,this 25 day of April 1916.

yCHARLES O. WYMAN. 

